Nuprl Lemma : Rice-theorem-for-Type_2

∀F:Type ⟶ 𝔹. ((∀X,Y:Type.  (X ~ Y ⇒ F X = F Y)) ⇒ (∀X,Y:Type.  (F X = F Y ∨ (∀f:ℕ ⟶ 𝔹. Dec(∀n:ℕ. f n = ff)))))


Proof




Definitions occuring in Statement :  equipollent: A ~ B,  nat: ℕ,  bfalse: ff,  bool: 𝔹,  decidable: Dec(P),  all: ∀x:A. B[x],  implies: P ⇒ Q,  or: P ∨ Q,  apply: f a,  function: x:A ⟶ B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  implies: P ⇒ Q,  or: P ∨ Q,  prop: ℙ,  uall: ∀[x:A]. B[x],  so_lambda: λ2x.t[x],  so_apply: x[s],  guard: {T},  exists: ∃x:A. B[x],  and: P ∧ Q,  nat-inf: ℕ∞,  nat: ℕ,  ge: i ≥ j ,  decidable: Dec(P),  uimplies: b supposing a,  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  not: ¬A,  top: Top,  subtype_rel: A ⊆r B,  le: A ≤ B,  less_than': less_than'(a;b),  uiff: uiff(P;Q),  rev_uimplies: rev_uimplies(P;Q),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  int_seg: {i..j-},  lelt: i ≤ j < k,  squash: ↓T,  nat2inf: n∞,  less_than: a < b,  sq_type: SQType(T),  assert: ↑b,  ifthenelse: if b then t else f fi ,  btrue: tt,  true: True,  bool: 𝔹,  unit: Unit,  it: ⋅,  bfalse: ff,  bnot: ¬bb,  nat-inf-infinity: ∞
Lemmas referenced :  Rice-theorem-for-Type_1,  all_wf,  nat_wf,  bool_wf,  decidable_wf,  equal-wf-T-base,  exists_wf,  nat-inf_wf,  not_wf,  assert_wf,  nat2inf_wf,  nat-inf-infinity_wf,  equal_wf,  equipollent_wf,  bnot_wf,  b-exists_wf,  nat_properties,  decidable__le,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermAdd_wf,  itermVar_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_add_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  le_wf,  int_seg_subtype_nat,  false_wf,  int_seg_wf,  assert_of_bnot,  assert-b-exists,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  lelt_wf,  int_seg_properties,  decidable__equal_int,  subtract_wf,  int_seg_subtype,  itermSubtract_wf,  intformeq_wf,  int_term_value_subtract_lemma,  int_formula_prop_eq_lemma,  set_wf,  less_than_wf,  primrec-wf2,  decidable__exists_int_seg,  decidable__equal_bool,  btrue_wf,  subtract-add-cancel,  iff_imp_equal_bool,  lt_int_wf,  assert_of_lt_int,  iff_wf,  subtype_base_sq,  bool_subtype_base,  true_wf,  eqtt_to_assert,  eqff_to_assert,  bool_cases_sqequal,  assert-bnot,  assert_functionality_wrt_uiff,  bfalse_wf,  assert_elim,  btrue_neq_bfalse
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  independent_functionElimination,  unionElimination,  inlFormation,  isectElimination,  functionEquality,  sqequalRule,  lambdaEquality,  applyEquality,  functionExtensionality,  baseClosed,  inrFormation,  productElimination,  productEquality,  universeEquality,  cumulativity,  instantiate,  dependent_set_memberEquality,  addEquality,  setElimination,  rename,  because_Cache,  natural_numberEquality,  independent_isectElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  promote_hyp,  addLevel,  impliesFunctionality,  equalityTransitivity,  equalitySymmetry,  applyLambdaEquality,  levelHypothesis,  hypothesis_subsumption,  imageMemberEquality,  imageElimination,  impliesLevelFunctionality,  equalityElimination,  hyp_replacement

Latex:
\mforall{}F:Type  {}\mrightarrow{}  \mBbbB{}
    ((\mforall{}X,Y:Type.    (X  \msim{}  Y  {}\mRightarrow{}  F  X  =  F  Y))
    {}\mRightarrow{}  (\mforall{}X,Y:Type.    (F  X  =  F  Y  \mvee{}  (\mforall{}f:\mBbbN{}  {}\mrightarrow{}  \mBbbB{}.  Dec(\mforall{}n:\mBbbN{}.  f  n  =  ff)))))



Date html generated: 2017_10_01-AM-08_29_44
Last ObjectModification: 2017_07_26-PM-04_24_07

Theory : basic


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